Subsoil tilling machine



1940- B. VALE 2,212,136

SUBSOIL TILLING MACHINE Filed April 11, 1938 2 Sheets-Sheet l FIG. I. I

INVENTOR.

Aug. 20, 1940. B VALE 2,212,136

SUBSOIL TILLING MACHINE Filed April 11, 1938 2 Sheets-Sheet 2 F I G. 3.

k$wnm 7 2 o o o n Patented Aug. 20, 1940* UNITED STATES PATENT OFFICE 9 Claims.

This invention relates to improvements in subsoil tilling machines and more particularly, to the construction and arrangement of the cutting means, and also to the method of conserving mois- 6 ture and preventing soil erosion.

Among the objects of the invention is to accomplish subsoil tillage with minimal draft resistance and maximal speed.

Another object is to pulverize the subsoil, break 10 up plow sole and hard pan strata, and increase the moisture capacity of the soil.

Another object is to prevent soil erosion and run-off on sloping land.

A further object is to provide dry tillage prior Other objects and advantages will appear as the description progresses.

In the specification and the accompanying drawings, the invention is disclosed in its present preferred form. But it is to be understood that it is not limited to this form because it may be .embodied in modifications within the purview of the claims following the description.

In the two sheets of drawings:

Fig. 1 is a plan view from above of a tilling machine constructed in accordance with this invention.

Fig. 2 is a diagrammatic vertical section of the same, looking forward from about the transverse arrow II in Fig. 1.

Fig. 3 is a similar view of the same following the next trip around the land.

Fig. 4 is an enlarged detail in elevation from the land side of the helicoidal cutting blade.

35 Fig. 5 is a cross section of the bottom of the blade taken along the plane indicated at V in Fig. 4.

Fig. 6 is a front elevation of the rotary cutting head of i a suction dredge, or ditching machine.

In detail the construction illustrated in the drawings, referring first to Fig. 1, comprises a more or less conventional mobile frame having the land side beam I, the intermediate beam 2 and the furrow side beam 3, joined at their overlapping front portions and cross braced as at 4 and 5.

The land side is supported upon the land wheel 6 journaled on the crank axle I pivoted in the bearing 8 fixed to the land beam I. The front 50 of the frame is supported on the furrow wheel 9,

journaled on the axle l0, vertically slidable in the bracket II that is adjustably fixed between the beams 2 and 3. The axle l has the steering lever in fixed thereon engaging the quadrant 55 II; or the front wheel 9 may be steered by any conventional means. The rear of the frame is supported upon the caster wheel l2 journaled on the axle l3 vertically pivoted at l4 in the bracket l fixed to the beam. The lever mechanisms l8 and I1 provide means for raising and lowering the front of the frame with respect to the wheels 6 and 9. The draft link I8 is attached to the front of the frame by the chain IS.

The helicoidal blades 20 and 2| extend obliquely between their respective beams i, 2, and 3, to which they are adjustably fixed by the bolts at 22, 23, 24, and 25. These blades are preferably concave in cross section, see Figs. 1 and 5, to form the beveled cutting edges 26 and 21, with the intermediate crown 28, which makes these edges practically self sharpening in their passage through the soil. When the edge 26 becomes nicked or dulled, the blade can be reversed to present the other cutting edge 21. The marginal flat planes 26' and 21', see Fig. 4, adjacent the cutting edges act as landsides" to hold the blades to a true cutting line, counteracting the tendency of any angular cutting edge to deviate from the line of draft.

These blades may be made of laminated stock with a hard steel layer on the convex crown side to form the cutting edges and 21 and the crown 28 with a tough layer on the concave or wearing side 26'2l'. For dry tilling the blade is made with a crown layer of high speed steel which will maintain a cutting edge at red heat.

This invention operates substantially as follows:

The levers l6 and I1 are elevated to lower the front of the frame, causing the cutting edges 26-26 to enter the ground as the machine is drawn forward. When the blades have reached the desired depth, the levers l6 and I! are set to prevent further'penetration. The rear wheel l2 runs in the open furrow Ca: on the subsoil C pulverized by the blade 2! which it follows. During this first trip the yoke 29, see Fig. 1, extends through the hole 30 also, to hold the axle I3 in the line of draft, except when making the initial left turn.

In succeeding trips around the land being tilled, the front wheel 9 follows the track Ax made by the rear wheel i2 during the prior trip. The frame is then leveled by manipulating thelevers l6, l1 and adjusting the axle pivot at I4 controlling the height of the frame at the rear relative to the wheel i 2. The yoke 29 is then placed as in Fig. 1 to permit the wheel [2 to caster on' the pivot id in making left turns, but stopping the axle from swinging out of the line of draft to the right. During succeeding left turns it is unnecessary to steer the front wheel 9 which will slide around except under unusual conditions.

The concavity of the blades and II increases the displacement about one inch, more or less, according to the result desired. The crown 28 at the entrance portion of the blade moves the furrow slice to the left; the bottom portion lifts it, while the rear portion shifts it to the right.

This distortion of the furrow slice vertically and laterally has a disintegrating, pulverizing, and clearingeifect on the slice of soil severed by the blade with no incidental compressive effect.

A gang or multiple tilling machine or plow= is disclosed to show the expansive capacity by duplicating the assembly of the intermediate beam 2. It is obvious that a "sulky" unit, as assembled on beams I and 3,-will operate in like manner.

If it is desired to divide the furrow slices horizontally, the conventional plow bottoms 3| and 32 may be combined with the frame as in Fig. 1.

In operation, the top furrow slice B, Fig. 2, is about to be severed by the plow bottom 3| and turned upside down into the open furrow at A1: behind the front wheel 9, see B", Fig. 3.

The plow bottom 32 cuts and turns the top furrow slice C, Fig. 2, into the open furrow above 13 as indicated at C" in Fig. 3. This leaves the open furrow Cm above C, see Fig. 3, to guide the front wheel 9 during subsequent trips around the land to the left.

The ends 31 and 32' of the plow shares out off the tops of the intermediate segments D between the furrows.

As indicated in Fig. 2, the helicoidal blades leave a channeled subsoil base between D-D adapted to retain excess rainfall and prevent washing away or lateral sliding of the top soil. This terrace eifect makes it possible to irrigate sloping lands, since the contiguous channels between the segments D-D filled with pulverized soil will absorb and retain artificial irrigation scientifically applied thereto with respect to the absorbent capacity of the soil loosened by this invention. Water thus conserved will sink, leach down alkali, and restore exhausted water tables. Surface water will not stand on deeply pulverized soil, which prevents scalding, caking, and sterilization of the top soil when irrigated in hot weather.

Attention is directed to the easy shearing angle of the cutting edge 26 of the helicoidal blade, and the relatively low resistance to its passage through the soil, as compared with the conventional plowing practice of cutting, lifting, turning, and laterally transferring a heavy furrow slice when moist enough to plow. Except to bury trash, it is not always desirable to bring the under soil to the top.

Subsoil pulverization, as in the present in- .helicoid and stance, should not be confused with the mere breaking up of the subsoil into large clods, which in some soils will not disintegrate, leaving large air spaces deleterious to root growth.

In instances where wide segments D are un- 15 I desirable, the radius of the blade curves can be increased or the loop otherwise shaped to diminish these segments to any desirable extent: see dotted lines D in Fig. 2.

The helicoidal blades described are equally 1 applicable to rotary cutting heads for ditching machines, suction dredges, and the like, as shown in Fig. 6. The rotary head 33 mounted upon the. driven shaft 34 has the blades 35 to fixed to the T shape heads 4| on their respective spokes 1 42. While a peripheral cutter is shown, the extension of the tangential ends of the blades toward the axis would give a substantially conical end cutter in addition to the peripheral helix, without departing from the spirit of the invention.

The invention is a useful accessory for use ahead of graders, land levelers, scrapers, bulldozers, listers, ditching machines, and wherever loose dirt is desirable.

, Throughout this specification and the claims,

helicoidal are employed to describe any skew curve having a shape approaching that of a helix.

Having thus described this invention, what I claim and desire to secure by Letters Patent is:

1. A substantially helicoidal cutting blade having a concave exterior surface.

2. A cutting blade in the form of a segmental helix with opposed cutting edges and having a raised longitudinal portion between said edges.

3. A subsoil tilling machine having a mobile frame; and a substantially helicoidal cutting blade having both its ends attached to said frame.

4. A tilling machine having a substantially helicoidal cutting blade; and a plow bottom arranged above the lower portion of said blade.

5. A tilling machine having a substantially helicoidal cutting blade; and a plow bottom arranged above the lower portion of said blade and to the rear of the leading edge thereof.

6. A tilling machine having a substantially helicoidal cutting blade and means for lifting and turning the furrow slice cut by said blade.

7. A helicoidal cutting blade having end portions tangential to the helicoid and lying in substantially parallel planes.

8. A subsoil cutting blade having a curved central portion with its outer surface substantially parallel with the axis of the central curved por- 5 tion and the line of draft.

9. A subsoil cutting blade having a curved central portion with its ends tangential thereto and oblique to the axis of said curved central portion.

BALDWIN VALE. 

